package com.ccsoft.leetcode.service;

import org.springframework.stereotype.Service;

/**
 * 21. 合并两个有序链表
 */
@Service
public class MergeTwoList {
    public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
        if( l1 == null ) return l2;
        if( l2 == null ) return l1;

        if( l1.val < l2.val ){
            l1.next = mergeTwoLists(l1.next,l2);
            return l1;
        }else{
            l2.next = mergeTwoLists(l1,l2.next);
            return l2;
        }
    }

    public class ListNode {
        int val;
        ListNode next;
        ListNode() {}
        ListNode(int val) { this.val = val; }
        ListNode(int val, ListNode next) { this.val = val; this.next = next; }
    }
}

